Artists such as Sam Hui and Roman Tam were among the first singers to popularize songs written and sung in Cantonese around that time. Much Canto-pop songs follow a rhyming format in its lyrics. This popularity, combined with slick marketing of the songs and its artists, lead to the development of a local popular music and entertainment industry that was not only popular in Hong Kong, which spread to other Chinese communities in Southeast Asia and beyond.
Artists in the 1980s that rode and strengthed the Canto pop industry included Alan Tam, Kenny Bee, Leslie Chueng, Anita Mui. The 1990s saw the emergence of artists such as the Four Heavenly Kings - Jacky Cheung, Andy Lau, Leon Lai, and Aaron Kwok. Today's artists include Sammi Cheng, Twins, Nicholas Tse, Eason Chan.
It's a pretty structured and manufactured industry -- stars get the buildup by their recording companies, they make lots of public apperances, and put on concerts at the Hong Kong Coliseum, often for days on end. They also frequently are cast in locally made movies to take advantage of their star power.
Much of the lyrics are often sappy and critically slammed as superficial. Some of them were covered from Japanese songs with local writers putting them to Chinese lyrics. They are, however, fairly easy to sing, and are often a staple of the karaoke lounge.
Many Cantopop stars, to take advantage of the markets in the PRC and Taiwan, will often record songs in Mandarin, and make appearances there as well, as well as areas such as Singapore, Malaysia and North America.
Cantopop is sugar for the ears.